Board former



Nov. 9, 196s R. F. KozlcH 3,216,891

BOARD FORMER Filed Feb. 25. 1963 INVENTQR gado/f fr" ,602/ ab United States Patent O The present invention relates to improvements in paper machines and more particularly to an improved machine for dewatering and forming board stock to form paper board.

The invention contemplates the provision of a porous Vforming cylinder with a forming wire trained thereover to form a web or layer of board on the uprunning side of the Wire on the cylinder. Dewatering of the board web is accomplished in part by vacuum means within the cylinder and a porous wire fabric belt is positioned to form a dewatering means coacting with the wire and cylinder by forming a squeeze area on the uprunning side of the cylinder engaging the upper surface of the board web. The fabric belt continues to follow the wire squeezing the board web therebetween along a horizontal linear run of the wire with a slice blade removing water from the inner side of the belt opposite the squeeze area and with a vacuum box positioned immediately following the squeeze area and extending along the horizontal run from the location where the forming wire leaves the forming cylinder.

In board forming machines a relatively high consistency stock of 2-5 percent is used and the machines often run at a slower speed relative to a conventional Fourdrinier type of machine. However, it is essential that the board be formed with an effective dewatering and with a uniform distribution of fibers with a uniform surface. This will insure affording strength to the board and insure smooth surface for a multiply board particularly where a iinished surface is applied.

Accordingly, an object of the present invention is to provide an improved forming and dewatering mechanism for forming paper board which achieves an improved board structure of uniform ber distribution and arrangement and with a more uniform and smooth outer surface to achieve a board of superior strength.

A further object of the invention is to provide an improved paper board forming and dewatering mechanism which has a more effective dewatering function to enable formation at higher speeds and to permit formation of paper board over a greater range of thicknesses.

A still further object of the invention is to provide an improved paper board forming machine wherein an improved board product is achieved by dewatering from both surfaces of the board and wherein dewatering is accomplished over a limited linear travel of the board.

Another object of the invention is to provide a machine of the above general description with improved attendant mechanisms coacting with the dewatering mechanism for the formation of an improved board and for improved more stable reliable operation of the machine.

A still further object of the invention is to provide an improved board forming and dewaterin g mechanism which is capable of forming a superior board with a greater range of fibrous materials for making up the stock and which is capable of operating with lower grade stock materials.

Other objects, advantages and features will become more apparent with the teaching of the principles of the invention in connection with the disclosure of the preferred embodiment thereof in the specification, claims and drawings, in which the ligure of the drawing is a side elevational view shown partially in section and in somewhat schematic form of a board forming machine constructed and operating in accordance with the principles of the present invention.

On the drawing:

A hollow forming cylinder 10 is horizontally positioned for rotation about its horizontal axis and has a porous shell or surface. Trained over the forming cylinder is a continuous short forming wire 11 for forming a web or layer of paper board B on its outer surface.

The wire is carried downwardly into paper stock S in a vat 12 which houses the lower portion of the forming cylinder 10 and envelops the lower portion of the forming wire 11 with stock. The stock is formed of suitable material in a water suspension and usually relatively heavy consistency of the order of 2-5 percent is employed of paper pulp or reprocessed stock or other suitable fibrous materials. The finished board coming olf of the wet end of the machine as shown will have a thickness of 1A inch to 5/8 inch.

Within the vat 12 are vat agitators such as 14 of suitable types which may be elongated partially opened or vaned cylinders driven for maintaining the stock in uniform suspension.

Stock is supplied to the vat through suitable means such as shown schematically at 15 to maintain a desired level of stock within the vat.

Within the forming cylinder a vacuum is formed such as by series of annular arranged separate vacuum boxes 21 connected to a suitable vacuum source, not shown. A board web B forms on the wire within the vat and the wire emerges from the vat on the uprunning side forming an uprunning run 11a which leads to a linear horizontal run 11b.

It may be desirous to employ a brush roll 16 for lightly engaging the outer surface of the board B on the uprunning side of the cylinder 10. The brush roll is driven in rotation in a surface direction opposite to that of the traveling forming wire 11 so that it will smooth down any lumps or rises on the outer surface of the board B. Any material removed will be thrown oif downwardly into a catch pan 17.

Means are provided for cleaning the forming wire 11 such as by water shower 18. The wire is guided during its travel away from the forming cylinder 10 by a return guide roll 19 which determines the linear run 11b and a return tensioning roll 20. The traveling forming wire 11 may be suitably driven such as by driving the forming cylinder or by driving the return roll 19.

Above the forming cylinder and forming wire is a porous wire fabric dewatering belt 21. The belt coacts with the forming wire by engaging the outer surface of the board B over a critical path of travel squeezing the board therebetween and coacting with the cylinder to improve removal of water into the cylinder 10, and also coacting with the forming wi-re 11 and removing the water upwardly through the belt 21.

The belt first engages the board on the uprunning side of the cylinder 10 at a pressure point or area P where the board is squeezed downwardly toward the backing force of the cylinder 10. This smooths the board, aids in distribution of the fibers which have been matted upon the cylinder, and helps insure that the board will be of uniform thickness and removes any lumps or rises. It also squeezes the water from the cylinder aiding the inwardly directed suction of the suction boxes 21a. In addition, water will be squeezed from the upper surface of the board to force itself through the porous fabric belt 21 and Water on the upper surface of the belt will be doctored off by a doctor or a slice blade 28. The slice blade leads upwardly away from the belt 21 with its leading edge in close adjacency with the belt, and water will travel up the blade into a collecting pan 29, with a shield 28a shown above the blade 28.

The belt is guided and held against the wire 11 at the pressure point P by a roll 24. It travels along the upper surface of the board B above the wire along the linear run 11b of the wire and is held against the board by a roll 25 which may be a porous dandy roll. The belt 21 is then guided upwardly to separate from the wire and from the board thereon by return rolls 23 which lead it back in its continuous loop to the roll 24.

At the location where the belt 21 leaves its uprunning side of the cylinder at the top of the cylinder 10, which is where it begins the linear horizontal run, extending toward where the forming wire 11 leaves the cylinder 10, is positioned means for drawing water upwardly through the board B. A suction box 30 is located above the belt provided with suction means, not shown, for dewatering the board B in an upward direction. This aids in further distribution of fibers and improved dewatering.

The porous belt 21 may be cleaned as by a shower 32 directing jets of water through the belt into a catch pan 31. If desired, the shower may also be placed on the inner surface of the belt.

The dewatered web leaves the wire 11 over a transfer table 26 and supporting rolls 27 to travel to a press section of the machine.

In operation, the continuous supply of stock is fed to the vat 12 through a supply line 15 and the board web B is formed on the traveling forming wire 11 as it emerges from the stock S in the vat on the uprunning side 11a of the cylinder 10. The partially dewatered board enters a pressure a-rea P where it is pressed against the forming wire 11 by a roll 24 carrying the fabric upper dewatering belt 21. Water pressed through the belt is collected on a slice blade 28 and adidtional water is removed along a linear run 11b through an inverted vacuum box 30.

Thus, it will be seen that I have provided an improved board forming and dewatering mechanism which meets the objectives and advantages above set forth. The method of operating on the board with the mechanism shown provides an improved paper board and enables making a board of much greater strength and uniformity than heretofore thought possible.

The drawings and specification present a detailed disclosure of the preferred embodiments of the invention, and it is to be understood that the invention is not limited to the specific forms disclosed, but covers all modifications, changes and alternative constructions and methods falling within the scope of the principles taught by the invention.

I claim as my invention:

1.` A device for forming paper board comprising in combination,

a hollow annular porous forming cylinder for continuous rotation to form a board web,

a stock vat surrounding the lower portion of the cylinder,

means for supplying stock to the vat outside of the cylinder, Y

a forming wire trained over the cylinder and having a guide roll therein for training the wire into a linear run of forming wire at the end of the uprunning side of the cylinder,

means for forming a suction within the cylinder to dewater the board web formed on the uprunning side of the cylinder on the outer surface of the wi-re,

a wire cleaner shower within the forming wire as it travels downwardly from the guide roll to the cylinder,

a dewatering fabric belt positioned above the linear run of the wire to engage the board web on said linear run and wrapping a portion of the uprunning side of d the forming cylinder for pressing water from the web on the forming wire,

first means removing water from the inner surface of the belt at said wrapped portion,

and second means for drawing water upwardly through the belt for dewatering the web on said linear run.

2` A device for forming paper board comprising in cornbination,

a hollow annular porous forming cylinder for continuous rotation to form a board web,

a stock vat surrounding the lower portion of the cylinder,

means for supplying stock to the vat outside of the cylinder,

a forming wire trained over the cylinder and having a guide roll therein for training the wire into a linear run `of forming wire at the end of the uprunning side of the cylinder, v

means for forming a suction within the cylinder to de- Water the board web formed on the uprunning side of the cylinder on the outer surface of the wire,

av porous belt positioned above the linear run of wire and traveling therewith positioned to engage the board web on the wire,

positioning rolls within the belt directing the belt into compressing engagement with the web on the wire wrapping a portion of the cylinder on the uprunning side of the cylinder to form an arcuate path opposite the forming wire leading into the linear run,

rst means removing water from the inner surface of the belt at the wrapped portion of the cylinder,

and second means for drawing water upwardly through the belt for dewaterng the web on said run.

3. A device for forming paper board comprising in combination,

a hollow annular porous forming cylinder for continuous rotation to form a board web,

a stock vat surrounding the lower portion of the cylinder, means for supplying stock to the vat outside of the cylinder,

a forming wire trained over the cylinder and having a guide roll therein for training the wire into a linear run of forming wire at the end of the uprunning side of the cylinder,

means for forming a suction within the cylinder to dewater the board web formed on the uprunning side of the cylinder ron the outer surface of the wire,

a pourous belt positioned above the linear run of wire and traveling therewith positioned to engage the board web on the wire,

positioning rolls within the belt directing the belt into compressing engagement with the web on the wire on the uprunning side of the cylinder to form an arcuate path opposite the forming wire leading into the linear run at the end of the uprunning side,

first means within the belt removing water from the upper inner surface of the belt on said uprunning side,

and second means for drawing water upwardly through the belt for dewatering the web on said run,

and means for cleaning the dewatering belt after it has passed the linear run.

4. A device for forming paper board comprising in combination,

a hollow annular porous forming cylinder for continuous rotation to form a board web,

a stock vat surrounding the lower portion of the cylinder, means for supplying stock to the vat outside of the cylinder,

a forming wire trained over the cylinder and having a guide roll therein for training the wire into a linear run of forming wire at the end of the uprunning side of the cylinder,

means for forming a suction within the cylinder to dewater the board web formed on the uprunning side of the cylinder on the outer surface of the wire,

a porous belt positioned above the linear run of wire and traveling therewith .positioned to engage the board web on the wire,

positioning rolls within the belt directing the belt into compressing engagement with the web on the Wire on the uprunning side of the cylinder to form an arcuate path opposite the forming wire leading into the linear run at the end of the uprunning side,

means inside the belt opposite said uprunning side removing water from the inner surface of the belt,

and a suction box within said belt extending along said linear run from the beginning of the run when the wire separates from the cylinder.

5. A mechanism for forming paper board comprising in combination, v

a hollow horizontal rotatable pervious forming cylinder,

a stock vat housing the lower portion of the cylinder,

means for supplying stock to the vat outside of the cylinder,

a forming wire looped over the cylinder,

a guide roll for the forming wire defining a linear run of forming wire at the end of the uprunning side of the cylinder,

means for forming a suction within the cylinder to dewater a board web formed on the uprunning side of the cylinder on the outer surface of the wire,

a dewatering pervious fabric belt positioned above the linear run of the wire and positioned to wrap a portion of the cylinder and then extend parallel to the run to engage and compress the hoard `web on said cylinder and on said run,

first means on the inside of the belt on the uprunning side removing water from inside the belt,

second means for drawing water upwardly through the belt for dewatering the web on said run,

and a transfer table following said linear run for removing the formed board.

6. A device for forming paper board comprising in combination,

a hollow annular porous forming cylinder for continuous rotation to form a board web,

a stock vat surrounding the lower portion of the cylinder,

means for supplying stock to the vat outside of the cylinder,

a forming wire trained over the `cylinder and having a guide roll therein for training the wire int-o a linear run of forming wire at the end of the uprunning side of the cylinder,

means for forming a suction within the cylinder to dewater the board web formed on the uprunning side of the cylinder on the outer surface of the wire,

a porous belt positioned above the wire on the uprunning side of the cylinder and forming a squeeze point between the belt and wire and extending along the linear run of the wire,

a slice blade on the inner side of the belt having a leading edge substantially against the belt at said 6 squeeze point and leading away from the belt in `the direction of belt travel removing water from within the belt located on said uprunning side. and means for drawing water upward-ly through the belt for dewatering the web along said linear run.

7. A mechanism for forming paper board comprising in combination,

a hollow horizontal pervious forming cylinder rotatable about a horizontal axis,

a stock vat housing the lower portion of the cylinder,

vat agitators within said vat,

means for supplying stock to the vat outside of the cylinders,

a forming wire trained over the cylinder and having a horizontal linear run extending from the uppermost portion of the cylinder,

a guide roll within the forming wire defining said horizontal run,

a plurality of vacuum boxes arranged circumferentially adjacent the inner surface of the cylinder for drawing water through the screen and forming a board web on the screen surface,

a forming wire shower within the screen for cleaning positioned on the downrunning side of the screen as it travels from the guide roll to the cylinder,

a brush roll on the uprunning side of the cylinder forming a nip therewith with the surfaces moving in opposite direction in said nip,

a catch pan below said brush roll for receiving particles removed from the board web by the brush roll,

a pervious wire fabric belt on the upper side yof the forming wire forming a squeeze point on the uprunning side of the cylinder and extending a distance along the horizontal run of the wire,

a suction box within the belt along said horizontal run of the wire,

a suction box within the belt along said horizontal run following said squeeze point,

a slice blade within the belt opposite said squeeze point leading away from the belt for carrying water from the inner surface thereof, v

a receiving pan for said slice blade,

a belt cleaning shower following said horizontal run,

and a transfer table receiving the formed board from said horizontal run.

References Cited by the Examiner UNITED STATES PATENTS 1,699,487 1/ 29 Hinde 162-318 1,724,154 8/29 Williams et al. 162-318 1,748,224 2/ 30 Hinde 162-318 1,804,560 5/ 30 Hussey 162-204 2,881,676 4/59 Thomas 162-203 2,911,039 11/59 Hornbostel et al. 162-303 2,995,186 8/61 De Montigny 162-317 3,056,719 10/62 Webster 162-318 DONALL H. SYLVESTER, Primary Examiner.

MORRIS O. WOLK, Examiner. 

1. A DEVICE FOR FORMING PAPER BOARD COMPRISING IN COMBINATION, A HOLLOW ANNULAR POROUS FORMING CYLINDER FOR CONTINUOUS ROTATION TO FORM A BOARD WEB, A STOCK VAT SURROUNDING THE LOWER PORTION OF THE CYLINDER, MEANS FOR SUPPLYING STOCK TO THE VAT OUTSIDE OF THE CYLINDER, A FORMING WIRE TRAINED OVER THE CYLINDER AND HAVING A GUIDE ROLL THEREIN FOR TRAINING THE WIRE INTO A LINEAR RUN OF FORMING WIRE AT THE END OF THE UPRUNNING SIDE OF THE CYLINDER, MEANS FOR FORMING A SUCTION WITHIN THE CYLINDER TO DEWATER THE BOARD WEB FORMED ON THE UPRUNNING SIDE OF THE CYLINDER ON THE OUTER SURFACE OF THE WIRE, A WIRE CLEANER SHOWER WITHIN THE FORMING WIRE AS IT TRAVELS DOWNWARDLY FROM THE GUIDE ROLL TO THE CYLINDER, A DEWATERING FABRIC BELT POSITIONED ABOVE THE LINEAR RUN OF THE WIRE TO ENGAGE THE BOARD WEB ON SAID LINEAR RUN AND WRAPPING A PORTION OF THE UPRUNNING SIDE OF THE FORMING CYLINDER FOR PRESSING WATER FROM THE WEB ON THE FORMING WIRE, FIRST MEANS REMOVING WATE FROM THE INNER SURFACE OF THE BELT AT SAID WRAPPED PORTION, AND SECOND MEANS FOR DRAWING WATR UPWARDLY THROUGH THE BELT FOR DEWATERING THE WEB ON SAID LINEAR RUN. 